4/ Using a simple ML model trained on our data, we inferred rates for all ≈68,000 known rubiscos based on sequences. Predictions suggest the same story: after 3.5 billion years of evolution, nature’s carbon-fixing engine runs at best at ≈30 reactions per second… and that’s it.

3/ The faster rubiscos (15–30 s⁻¹) are found in a few sequence clusters, usually associated with microaerobic environments or CO₂-concentrating mechanisms. Even exploring these groups further, we find a plateau: no faster variants beyond ≈30 s⁻¹. Has evolution hit a ceiling?

2/ We systematically measured rubiscos from the three domains of life, doubling known kinetic diversity. Despite big genetic variation, all stay in a narrow range: most fix CO₂ at <10 s⁻¹, none exceed ≈30 s⁻¹ at 30 °C, far slower than typical metabolic enzymes (≈80 s⁻¹).

1/ How fast can life’s most important enzyme go? Rubisco catalyzes nearly all carbon fixation on Earth, feeding the biosphere. In our new @PNAS study, we explored ≈500 rubiscos across the tree of life to see if any are actually fast (Spoiler: they aren’t) pnas.org/doi/10.1073/pnas.25…

4/ The awe-inspiring African Serengeti migration, with ~1 million wildebeest, zebras & gazelles, barely moves as much biomass as attending the FIFA World Cup or an annual Hajj. But the biggest migration of all? The daily vertical dance of plankton & tiny fish in the ocean.

3/ The ocean still holds the most biomass movement on Earth, but it has been down 60% since 1850, mainly from over-fishing and whaling. Meanwhile, human biomass movement rose by 4000% driven by industrialization and population growth.

2/ Biomass movement = the total mass of animal species × the distance it travels per year. We used hundreds of studies and datasets to quantify it globally. On land, birds, mammals & insects move most, but their combined biomass movement is ~40× smaller than that of humans.

1/ Earth is teeming with life on the move, from whales crossing oceans to humans commuting to work. But how does the movement of animals compare to humanity's? Our new study in @NatureEcoEvo answers just that! nature.com/articles/s41559-0…

3/ Zooming in on marine mammals, their global biomass declined by ≈70% since the 1850s, despite a moderate increase in recent decades. This provides a broader perspective to observed extinctions, with ≈2% of marine mammal species recorded as extinct during the same period

2/ We estimate that wild mammal biomass globally in 1850 was ≈200 Mt, roughly equal to that of humans and their domesticated mammals combined at the time. Since then, human and domesticated mammal biomass has risen to ≈1100 Mt, while wild mammal biomass decreased to ≈60 Mt